While trying to find out why winter is still persisting in Dunwyn alone, Sunni, Tummi and Cubbi encounter a frost giant named Chillbeard who uses a "wind horn" to freeze everything. The cubs wonder why Chillbeard seems immature for the "Lord of Winter", wanting to play games instead of allowing spring to start.

Sunni saves a squirrel-like shapechanger called a boggle, from a hungry wolf and takes it back home. But a shape-changer - not to mention a whole family of them - tends to make a rather tedious pet!

When Gruffi breaks his foot, he stubbornly refuses to stay put, believing that the Glen would suffer if he doesn't remain active. His attitude doesn't improve when a rowdy bandit gang decides to make camp--right above the Gummi Glen abode.

A bird threatens the Gummiberry bushes and nobody will listen to Cubbi's ideas to get rid of it.

Grammi believes it is time to teach another Gummi Bear how to make Gummiberry juice. Sunni is chosen as the most eligible candidate, but is more into fashion and spending time with Calla. The Ogres kidnap Grammi and take her to Castle Drekmore, where Duke Igthorn attempts to coax the recipe for Gummiberry juice from her. When the Gummis go on a rescue mission, they request Sunni to follow and bring some Gummiberry juice, which Sunni does not know how to make because she failed to pay attention to Grammi's lessons.

The pompous wizard Don Gordo will not accept Zummi's help in finding his missing magic key, so a battle of magic ensues.

Sunni finds a baby cliff dragon with a hiccup, and a swig of Gummiberry juice only aggravates the problem.

A Slumber Sprite puts Gruffi to sleep, requiring Grammi and Cubbi to trek across hostile terrain to find the sprite and keep Gruffi from suffering nasty accidents.

Zummi finds a section of the Great Book of Gummi that contains advanced magic spells. However, this also signals Zorlok, an evil wizard whom the Great Gummis had imprisoned in a subterranean prison, that he can find the unlocking spell, then be free to inflict violence on all Gummi Bears the world over, then conquer the world. To do this, Zorlok creates a monster to steal the Great Book, causing Zummi, Grammi and Gruffi needing to track it down.

When Gusto invents a decoy to lure ogres away from Gummi Glen, it fools the ogres, but also attracts the humans, who start looking around the forest. It is up to Gruffi and Gusto to save the glen.

A Gigglin causes a practical joke spree in the Glen. Will this stop the dam from being built in time to stop the water from flooding in?

After the egg of a griffin rolls free, Cubbi gets mistaken for the baby whilst Gruffi has to deal with the actual baby griffin who thinks he is his father. Can Gruffi and Cubbi make the switch without facing the wrath of the mother griffin?

An accidental mixture of Gummiberry juice and baby powder reduces Igthorn's Ogre troops to infants, and Grammi takes in one of these babies to raise it for the better.

Dunwyn's most famous paladin, Sir Victor, pays a visit to King Gregor's court. But the White Knight bears a secret which makes him an easy target for extortion by Igthorn.

Inspired by some old stories, Cubby constructs a flight pack and races off into the clouds to find the legendary Aerials. Unfortunately, the Aerials are not like the old Gummi stories described, in more than one way.

Tummi finds a Gummarine, an ancient seagoing vessel that can take the Gummies to New Gumbria, where they can meet other Gummies. However, their plans are quickly derailed when Duke Igthorn captures the ship and uses it to attack King Gregor.

Gusto creates a lifelike stone statue of Zummi, then persuades Zummi to come to his workshop so he can create a better one. Meanwhile, Gruffi mistakes the statue for his friend, believing that Zummi has turned himself into stone - and so does Lady Bane.

The Trolls are on the loose again, and this time they've hijacked an ancient Gummi digging machine.

A message by Sir Thornberry lures both the Gummis and Igthorn back to Ursalia, where a new band of Gummis, the Barbics, have taken refuge. The new tenants, however, are mostly a rather unsociable bunch with a deep hatred for all humans. They seek the ultimate weapon in Ursalia to get revenge against the humans, and as it so happens, this weapon is close to falling into Igthorn's hands.

Grammi finds what seems to be a Gummi forced to work as a side show and takes him home to Gummi Glen, but Gruffi thinks there is something wrong with him. Are Gruffi's suspicions correct, or have they found another Gummi Bear?

The Gummis are nearly out of Gummiberry juice so Grammi needs to make more, but the spigot is stuck so Zummi, Grammi, Cubbi, and Cavin go to the pumping station to fix the problem. But they discover that the facility is near a maritime boundary that separates Dunwyn and Drekmore – where Duke Igthorn and his ogres live. They only have four bottles of Gummiberry juice left, that's one for each of them. Can they fix the problem and get back home safely to Gummi Glen without being noticed by the ogres?

Duke Igthorn hires a bounty hunter to catch a Gummi Bear. When he refuses to pay, the hunter locks up Ightorn, the ogres, and Cubbi in his castle.

Despite Gruffi's objections, Cubbi finds a wolf cub and raises it.

Igthorn and Tummi switch bodies on Tummi's birthday.

Cubbi accidentally wrecks Ursalia's water reservoir, leaving the ancient metropolis short of its most important commodity. While Gruffi, Ursa and Sir Thornberry keep bickering whilst following an ancient aqueduct to find out why the water flow has stopped, Gritty and Cubbi try to lasso and train a few ramas (an amalgam of ram and lama) to fetch water from the not-so-nearest river. But then Gritty tries to get revenge on a group of mountain shepherds for human crimes against the ancient Gummi Bears, and Cubbi has a hard time trying to persuade him otherwise.